DrayTek

The Vigor 2830 series wireless models come in two variations, single band and selectable dual-band. Single band models provide Wireless access in the 2.4Ghz band. Dual-band models can be set to operate in either the 2.4Ghz or 5.8Ghz band. the units do use different firmware, so it's important you can identify your unit if you ever want to download updated firmware.

Vigor 2830n-Plus / 2830Vn-Plus

All "Plus" models are dual band. You do not need to read further here.

Vigor 2830n / 2830Vn

Prior to approximately July 2011, the 'Plus' suffix was not used but all units were dual-band (there was no single band model yet). This does, however, mean that a Vigor 2830n or Vigor 2830Vn may be single or dual-band, depending on when it was purchased.

Checking the Actual Unit

On the underside of the Vigor2830 unit, if it's a wireless model it will have the wireless module listed on the underside:

 

Vigor 2830 Bottom Sticker

  Module 8 = Dual-Band

  Module 6 = Single-Band

Checking the Part No. (by box barcode)

If you have the router still in its box, you can check that. The actual printed box is the same for all models, but the silver barcode sticker is unique for each unit. The International Article Number ( EAN ) denotes the actual product type; it is shown as "E/N" in numeric and barcode form on the box label. Pay attention only to the E/N, not the product name or the serial number. Here are the E/N codes and wireless type for each Vigor 2830 series model:

 

Barcode Sticker on Side of box
Sticker on side of Box
E/N    Wireless Type   
   471 9853559 295    None
471 6779070 927 Single-Band
471 6779071 047 Single-Band
471 9853559 394 Dual-Band
471 9853559 493 Dual-Band

Checking the Unit from the Web interface

On a single band model, on the Wireless LAN setup menu you will only have settings for 802.11n and 802.11b. On dual-band models, you will have additional selections for 802.11 g/n/a and depending on your current firmware version, it may also state 5Ghz. If your router has a setting for 5Ghz or 802.11a then it is dual-band and you should use dual-band firmware.

The screenshot below shows 802.11a and 5Gz, so it's dual band.